When opening the cockpit in Wildfly an exception is thrown:

[...]
java.sql.SQLException: XAER_OUTSIDE: Some work is done outside global transaction.
[....]
### The error may exist in org/camunda/bpm/engine/impl/mapping/entity/ProcessDefinition.xml
### The error may involve org.camunda.bpm.engine.impl.persistence.entity.ProcessDefinitionEntity.selectProcessDefinition
### The error occurred while executing a query

It seems that the cockpit is misbehaving and running local transactions that conflicts with some xa-transactions. The problem may also involve autocommits and the jdbc driver? This problem in general is discussed here: http://forum.spring.io/forum/spring-projects/data/50569-jta-transaction-issue-with-mysql

The problem has been reproduced with the standalone wildfly distribution and the configuration (standalone.xml) is attached along with the complete stack trace.

The exception goes away if we add <no-tx-separate-pools /> to the pools config, but we don't want to do that as it creates another pool on the server.

I have also found another user seeing the same problem with version 7.5:
https://stackoverflow.com/questions/42384335/xa-datasource-and-cockpit